<!DOCTYPE html>
<html>
    <head><meta http-equiv="content-type" content="text/html" charset="utf-8">
    <title>test</title>
    </head>
    <body></body>
        <script type="text/javascript">
        debugger;
        
        let a = function (b){
            a= function () { return b };
                b=b+12;
                return b;
            }

            var result1 = a(23);    
            console.log(result1);
            var result2 = a(1111);
            console.log(result2);
        </script>

</html>